Church fires in the US are very common, but usually not arson or racially motivated

Investigators from the Bureau of Alcohol, Tobacco, Firearms and Explosives and the South Carolina Law Enforcement Division remove the remains of a door from the Mount Zion African Methodist Episcopal Church, Wednesday, July 1, 2015, in Greeleyville, S.C. The African-American church, which was burned down by the Ku Klux Klan in 1995, caught fire Tuesday night, but authorities said arson is not the cause. (Veasey Conway/The Morning News via AP) (The Associated Press)

Charred remains inside the Mount Zion African Methodist Episcopal church are illuminated early Wednesday, July 1, 2015, in Greeleyville, S.C. The African-American church, which was burned down by the Ku Klux Klan in 1995, caught fire Tuesday night, June 30, 2015. (Veasey Conway/The Morning News via AP) (The Associated Press)

A firefighter's jacket and helmet sit on a marker outside Mount Zion African Methodist Episcopal church, early Wednesday, July 1, 2015, in Greeleyville, S.C. The African-American church, which was burned down by the Ku Klux Klan in 1995, caught fire Tuesday night, June 30, 2015. (Veasey Conway/The Morning News via AP) (The Associated Press)

While investigators probe the cause of a fire that destroyed a rural black church in South Carolina, statistics show church fires aren't unusual and happen dozens of times a week across the nation.

Estimates from the National Fire Protection Association indicate that in the five years from 2007 through 2011, 31 houses of worship burned each week across the country. Arson was relatively rare, reported in only 16 percent of those fires.

Investigators are looking into what caused a fire Tuesday night at Mount Zion African Methodist Episcopal Church in Greeleyville. The same church was torched by members of the Ku Klux Klan 20 years ago.

A federal official has told The Associated Press that preliminary indications are that this week's fire was probably not arson. The official spoke on the condition of anonymity, because he wasn't authorized to discuss the case publicly.